Devices are known in the prior art in which organic light-emitting diodes, more simply denoted by the term “OLED diodes”, are controlled at a refresh frequency by control circuits comprised of transistors. Such control circuits allow a voltage to be applied across the terminals of the OLED diodes after a refresh operation, and for this voltage to be maintained until the next refresh operation. This is made possible by using the capacitance associated with NMOS transistors which are respectively coupled to anodes of the OLED diodes.
The control circuits include other MOS transistors which act as switches. These transistors are conducting during the refresh operation (which has a short duration), then are in a non-conducting state when the voltage is maintained between refresh operations. Current leakages may nevertheless appear within these transistors acting as a switch.
The effect of these leakage currents causes a drop in the voltage across the terminals of the OLED diodes, which progressively decreases starting from the moment when the transistors acting as switches go into the non-conducting state.
This drop in the voltage across the terminals of the OLED diodes is associated with a reduction in the light intensity emitted by the OLED diodes. If this reduction in light intensity is too great between two refresh operations, it may be noticed by the user looking at the matrix of active OLED pixels. This phenomenon is commonly denoted by those skilled in the art by the term “flicker”.
The period between two refresh operations is associated with a refresh frequency. In order to limit the appearance of the flicker phenomenon, those skilled in the art know that it is preferable to use a high refresh frequency, for example 50 or 60 Hz. These refresh frequencies have the drawback of being associated with an increase in electrical power consumption.